Bag folding system

ABSTRACT

An automated system is disclosed for folding vehicle air bags so that a small folded-bag profile and a desirable bag deployment pattern results. A machine having numerous moveable arms is controlled by a controller. An edge folding assembly (EFA) of the machine has five arms, including a center arm, two outer blades, and two outwardly facing U-channel forks, which reside between respective outer blades and the center arm. The EFA moves forward so that all of its five arms engage an unfolded air bag. The forks then raise upward to a level at which the outer blades are aligned with a gap between tines in the forks. The outer blades mesh with this gap causing two pleats to be formed in the edge of the bag. Pleat clamps then move inwardly sideways to engage the two pleats and form a third pleat. Then, the EFA is removed from the bag. The pleat clamps may clamp top and bottom sections of the bag together while tightly gripping the pleats. The bag is then inflated or otherwise pulled apart, except that the pleat clamps can prevent separation of the pleated section. Next, the pleat clamps move closer together to poke the pleats into the center of the separated bag. The bag is then collapsed or deflated, and the pleat clamps are withdrawn from the bag.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the folding of flexible,multi-layer, sheet-like articles, such as bags. More specifically, thepresent invention relates to folding vehicular air bags.

BACKGROUND OF THE INVENTION

Vehicular air bags are among the latest safety enhancements forautomobiles and other vehicles. Their use in vehicles is increasingdramatically. Generally, such air bags are located within a steeringwheel or column, dashboard, control panel, or other out-of-the-waylocation which is near a vehicle's occupant. Sensors located in thevehicle detect when a crash is occurring and activate the air bag(s).When activated, the air bags rapidly inflate between the vehicle'soccupant and a potentially injurious or deadly surface, such as asteering wheel. As the crash progresses, the force of the crash may hurlthe occupant toward the injurious or deadly surface, but the occupantfirst encounters the air bag, which prevents or otherwise lessens injuryto the occupant.

In order for the air bag to be effective, it must be stored in anout-of-the-way location until needed. Moreover, it must be stored insuch a manner that it can be rapidly activated to do its job. Due to thecontinual down-sizing of vehicles, the out-of-the-way locations whereair bags are typically located are usually rather small. Thus, an airbag must be folded into a small package so that it fits into a smalllocation. But, the technique used to fold the air bag affects itsdeployment when activated. To minimize the possibility of harm to avehicle occupant, the air bag preferably deploys evenly in a spreadingout (side-to-side) manner rather than shooting first toward one sidethen the other or shooting straight out then filling in fromside-to-side.

The conventional process for folding vehicular air bags relies almostexclusively on manual labor. This conventional process is plagued withproblems. For example, approximately 12 minutes are required to fold anair bag using manual labor. With the large number of air bags now beingused in vehicles, a tremendous amount of labor and expense is requiredto fold air bags. Moreover, the folding of air bags requires a largenumber of highly repetitive manual motions. Such repetitive motions arepotentially hazardous to the health of the manual laborers. In addition,such repetitive motions lead to boredom, which in turn leads to a poorperformance of the job.

Another problem relates to the consistency with which bags are foldedusing the conventional process. While some bags get folded acceptably,others tend to be folded using a less-than-optimal folding pattern or ina manner which results in an overly large package. This lack ofconsistency results in a considerable amount of rework, which isexpensive, and inconsistent bag deployment patterns, which may poseunnecessary dangers to vehicle occupants.

While a few automated processes have been developed to automaticallyfold air bags, the automated processes have their own problems. Inparticular, the folding of the air bag should not introduce contaminantsinto the bag. Such contaminants can possibly degrade the bag over timeand cause the air bag to be defective when needed. Accordingly,automated processes tend either to forego inflating the bag during thefolding process or to utilize extensive filtering to purify any airentering the bag during folding. When bag inflation is omitted, manydesirable fold patterns cannot be achieved. When bag inflating is usedto push top and bottom bag layers apart, large quantities of air must befiltered. Moreover, air pressures tend to excessively fluctuate whenparts of an air bag are tucked into an inflated portion of the bag. Airpressure increases experienced during such tucking operations canpotentially over-stress air bags.

SUMMARY OF THE INVENTION

Accordingly, it is an advantage of the present invention that anautomated system for folding air bags is provided.

Another advantage of the present invention is that a system for foldingbags quickly is provided.

Yet another advantage of the present invention is that a system forfolding air bags in a consistent fold pattern is provided.

Still another advantage of the present invention is that a system forfolding air bags to consistently achieve a desirable deployment patternis provided.

Still another advantage of the present invention is that a system forconsistently folding air bags to achieve a small folded-bag profile isprovided.

Another advantage of the present invention is that a system is providedwhich permits the tucking of one portion of an air bag into another partof the bag.

Another advantage of the present invention is that a system is providedwhich need not pressurize an air bag and which reduces air bagcontamination.

The above and other advantages of the present invention are carried outin one form by a method of automatically folding an air bag. The air bagcharacteristically has top and bottom sections, and the folding methodachieves a folded-bag profile that is suitable for vehicularinstallation along with effective bag deployment in the event of avehicle crash. The method calls for pulling the top section at a centralportion of the bag from the bottom section. When the top and bottomsections have been separated, an edge portion of the air bag is insertedinto the central portion between the top and bottom sections.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention may be derived byreferring to the detailed description and claims when considered inconnection with the figures, wherein like reference numbers refer tosimilar items throughout the figures, and:

FIG. 1 shows a perspective view of a preferred embodiment of the presentinvention in connection with an air bag and prior to a first stage inthe preferred process for folding the air bag;

FIG. 2 shows a cross sectional view of the preferred embodiment taken atline 2--2 of FIG. 1;

FIG. 3 shows a block diagram of the preferred embodiment of the presentinvention;

FIG. 4 shows a cross sectional view of the preferred embodiment of thepresent invention after a second stage in the preferred process forfolding the air bag;

FIG. 5 shows a cross sectional view of the preferred embodiment of thepresent invention after a third stage in the preferred process forfolding the air bag;

FIG. 6 shows a cross sectional view of the preferred embodiment of thepresent invention after a fourth stage in the preferred process forfolding the air bag;

FIG. 7 shows a cross sectional view of the preferred embodiment of thepresent Invention after a fifth stage in the preferred process forfolding the air bag;

FIG. 8 shows a cross sectional view of the preferred embodiment of thepresent Invention after a sixth stage in the preferred process forfolding the air bag;

FIG. 9 shows a cross sectional view of the preferred embodiment of thepresent invention after a seventh stage in the preferred process forfolding the air bag;

FIG. 10 shows a cross sectional view of the preferred embodiment of thepresent invention after an eighth stage in the preferred process forfolding the air bag;

FIG. 11 shows a cross sectional view of the preferred embodiment of thepresent invention after a ninth stage in the preferred process forfolding the air bag;

FIG. 12 shows a cross sectional view of the preferred embodiment of thepresent invention after a tenth stage in the preferred process forfolding the air bag;

FIG. 13 shows a cross sectional view of the preferred embodiment of thepresent invention after an eleventh stage in the preferred process forfolding the air bag;

FIG. 14 shows a cross sectional view of the preferred embodiment of thepresent invention after a twelfth stage in the preferred process forfolding the air bag;

FIG. 15 shows a cross sectional view of the preferred embodiment of thepresent invention after a thirteenth stage in the preferred process forfolding the air bag;

FIG. 16 shows a cross sectional view of the preferred embodiment of thepresent invention after a fourteenth stage in the preferred process forfolding the air bag;

FIG. 17 shows a cross sectional view of the preferred embodiment of thepresent invention after a fifteenth stage in the preferred process forfolding the air bag;

FIG. 18 shows a cross-sectional view of the air bag folded in accordancewith the preferred process;

FIGS. 19A-19F together show exemplary vertical folds which may beutilized to place the air bag in a final stage; and

FIGS. 20A-20C together show an alternate preferred process for foldingthe air bag.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description certain items are either similar to ormirror images of other items. This description distinguishes such itemsfrom their counterparts by the use of lower case alphabetic characters("a", "b", and so on) which are appended to a common reference number.When an alphabetic character is omitted, the description refers to anyone of such items or their counterparts individually or to all of themcollectively.

FIG. 1 shows a perspective view of a preferred embodiment of a bagfolding machine 10 configured in accordance with the present invention.FIG. 1 further shows a deflated air bag assembly 12 positioned onmachine 10. FIG. 1 illustrates the state of machine 10 and bag assembly12 prior to a first stage (discussed below) in a preferred process forfolding bag assembly 12.

Machine 10 includes a top blade 14, which is movable in a verticaldirection from an upright position, shown in FIG. 1, to a loweredposition, in which blade 14 closely overlies bag assembly 12. Thecentral region of blade 14 carries pins 16a, 16b, 16c, and another pinwhich is hidden from view in FIG. 1. Pins 16 couple to and extendperpendicularly away from blade 14. Furthermore, pins 16 are movablefrom a raised position relative to blade 14, shown in FIG. 1, to alowered position, discussed below. In viewing FIG. 1, pins 16a and 16breside on the right side of blade 14 while pin 16c and the hidden pinreside on the left. Elastic band 18a is looped around pins 16a and 16cunderneath blade 14, and elastic band 18b is looped around pin 16b andthe hidden pin underneath blade 14.

Machine 10 additionally includes an edge folding assembly (EFA) 20,which is shown positioned behind bag assembly 12 in FIG. 1. EFA 20 ismoveable from its rearward position shown in FIG. 1 to a forwardposition where it engages bag assembly 12.

EFA 20 carries five arms which move together between the rearward andforward positions. These five arms include a center arm 22, left andright fork arms 24a and 24b, respectively, and left and right outerblades 26a and 26b, respectively. Center arm 22 remains stationaryrelative to EFA 20. In other words, arm 22 moves only inward and outwardwith the entire EFA 20 and does not move any substantial distance eitherupward, downward, left, or right.

Fork arms 24 each reside between respective outer blades 26 and centerarm 22. Each fork 24 resembles a U-channel having an upper plate or tine28a and an opposing lower plate or tine 28b. For each fork 24, tines 28are spaced apart from one another by a gap 30, and the U-channelopening, hereinafter referred to as an entrance edge 32, faces away fromthe center of machine 10. Each fork 24 may move upward from its downwardposition, shown in FIG. 1, with respect to EFA 20. In other words, forks24 move forward and backward with the entire EFA 20 as well as upwardand downward.

Outer blades 26 are positioned vertically at a level slightly abovecenter arm 22. Each blade 26 is configured to move from an outwardposition, shown in FIG. 1, to an inward position with respect to EFA 20.As discussed in more detail below, when forks 24 are in their upwardpositions, gaps 30 are vertically aligned with outer blades 26, and whenouter blades 26 move to their inward position, they mesh with gaps 30.

Machine 10 additionally includes pleat clamps 34a and 34b located to theleft and right, respectively, of outer blades 26 from EFA 20 and atroughly the same vertical level as outer blades 26. FIG. 1 shows pleatclamps 34 in their extreme outer positions. However, pleat clamps 34 areeach movable to an intermediate position and an extreme inner position,as will be discussed below.

As a whole, pleat clamps 34 remain substantially stationary in thevertical dimension. However, each of pleat clamps 34 carries upper andlower plates or fingers 36a and 36b, respectively. The horizontal length(generally from left-to-right in FIG. 1) of fingers 36 is slightlygreater than the sum of the horizontal lengths of one outer blade 26 andone fork arm 24. Fingers 36 move vertically with respective to oneanother. FIG. 1 shows an opening 38 between fingers 36 at its widest. Asis discussed below, fingers 36 move vertically toward one another sothat opening 38 disappears and a clamping force is exerted betweenfingers 36. Fingers 36 additionally exhibit a position in which opening38 is very small and at which no clamping force is exerted betweenfingers 36.

Each of fingers 36 includes two notches 39 which accommodate pins 16, asdiscussed below. Notches 39 extend left-to-right from inward edges(facing the center of machine 10) of fingers 36 outward into theinterior of their corresponding fingers 36.

FIG. 1 shows air bag assembly 12 in a deflated, and unfolded state,which causes bag assembly 12 to roughly resemble a thin pancake. Inviewing bag assembly 12 vertically from bottom to top, assembly 12includes a base plate 40 secured to a sealed, flexible bag 42. Bag 42includes a bottom section 44, which attaches to base plate 40 and a topsection 46, which overlies bottom section 44 in the deflated stateillustrated in FIG. 1. In viewing bag 42 horizontally, left edge portion48a and right edge portion 48b are separated from one another by centralportion 50. Base plate 40 attaches to bag 42 only in the central regionof central portion 50 and not in end portions 48.

Base plate 40 of air bag assembly 12 couples to a worksurface 52 ofmachine 10. A base plate 40 includes a pneumatic passage which iscontinued through worksurface 52, through a valve arrangement 54, to avacuum reservoir 56 or the atmosphere at a vent 58. Those skilled in theart will appreciate that a filter (not shown) may be installed over vent58. Accordingly, valve 54 may be operated to pneumatically couple airbag assembly 12 to the atmosphere, seal air bag assembly 12, or applypneumatic vacuum to air bag assembly 12. A valve arrangement 55 couplesvacuum reservoir 56 to plenums 59a and 59b and to blade 14. Plenums 59reside underneath bag assembly 12 on opposing sides of worksurface 52.

FIG. 2 shows a cross sectional view of machine 10 at line 2--2 ofFIG. 1. In particular, FIG. 2 illustrates pneumatic plumbing of machine10. As illustrated in FIG. 2, top blade 14 is a hollow plenum whichpneumatically couples to vacuum reservoir 56 through a tube 110 andvalve 55 (see FIG. 1). A bottom surface 112 of blade 14 desirably has amultiplicity of small holes 114 therein to communicate vacuum suction orpressure from an interior 116 of blade 14 through bottom surface 112.

Plenums 59a and 59b are each hollow containers having substantially flattop surfaces 120a and 120b, respectively. Surfaces 120a and 120b eachhave a multiplicity of small holes 122a and 122b, respectively,distributed therethrough. Holes 122a and 122b extend between interiors124a and 124b, respectively, of plenums 59a and 59b and the exterior ofplenums 59a and 59b. Holes 122 allow vacuum suction or pressure to becommunicated across surfaces 120. Plenums 59a and 59b pneumaticallycouple through tubes 126a and 126b, respectively, and through valve 55to vacuum reservoir 56.

In addition, work surface 52, upon which base plate 40 (see FIG. 1) ofbag assembly 12 mounts, has a pneumatic passage 128 therethrough.Passage 128 pneumatically couples the interior of air bag assembly 12 tovalve 54 (see FIG. 1), and through valve 54 to either vacuum reservoir56 or atmospheric vent 58.

FIG. 3 shows a block diagram of the preferred embodiment of machine 10.As discussed above in connection with FIG. 1, numerous blades, arms, andfingers of machine 10 are moveable. FIG. 2 shows that machine 10 employsa controller 60 to coordinate such movements. Those skilled in the artwill appreciate that any suitable programmable controller, personalcomputer, or similar item may suffice for controller 60.

Controller 60 couples, through an appropriate control bus 62, tonumerous actuators and valves which control the above-discussedmovements. In particular, an actuator 64 mechanically couples to andcontrols the upward and downward movement of top blade 14; an actuator66 mechanically couples to and controls the upward and downwardmovements of pins 16; an actuator 68 mechanically couples to andcontrols the forward and backward movements of EFA 20; an actuator 70mechanically couples to and controls the upward and downward movementsof EFA forks 24; an actuator 72 mechanically couples to and controls theleft and right movements of EFA outer blades 26; an actuator 74mechanically couples to and controls the left and right movements ofpleat clamps 34; an actuator 76 mechanically couples to and controls theupward and downward movement of pleat clamp fingers 36; a valve actuator78 couples to valve 54 to close valve 54, or to control the applicationof vacuum to bag assembly 12; and a valve actuator 79 couples to valve55 to control the application of vacuum to the plenum of top blade 14and to plenums 59.

Those skilled in the art will appreciate that the precise programminginstructions and the nature of the control imparted through controller60 and actuators 64-79 has little bearing on the present invention,other than in accomplishing the below-discussed process. For example,while the preferred embodiment of the present invention primarily usespneumatic actuators, those skilled in the art may adapt hydraulic orsolenoid actuators to impart the above-discussed movements. Moreover,those skilled in the art will fully appreciate that limit or positionswitches or sensors may be employed in a conventional fashion withinmachine 10 to indicate to controller 60 when desired positions(discussed below) are achieved through such movements. Moreover,multiple actuators may be employed to move arms, such as EFA outerblades 26, individually rather than as a unit. And, other well knownmechanical devices, such as slides, levers, gears, belts, and the like,may be employed to transfer and guide the arm motions discussed herein.

FIG. 1 and FIGS. 4-17 together present various states or stages throughwhich machine 10 and air bag assembly 12 progress in making horizontalfolds in air bag 42. As discussed above, FIG. 1 illustrates machine 10and bag assembly 12 prior to a first stage in the horizontal foldingprocess. Prior to the first stage, center portion 50 of bag 42 issupported, but nothing supports edge portions 48 of bag 42. Thus, edgeportions 48 droop downward.

FIG. 4 illustrates machine 10 and bag assembly 12 after a second stage,which occurs immediately after the first stage. In the second stage, EFA20 moves forward where it engages bag 42. In particular, center arm 22of EFA 20 slides over central portion 50 of bag 42 and underneath topblade 14, EFA forks 24 move underneath corresponding edge portions 48 ofbag 42, and outer blades 26 move over bag 42. As shown in FIG. 4, due tothe droop in bag 42 forks 24a and 24b actually reside to the inside(right and left) of end portions 48a and 48b, respectively. For the samereason, outer blades 26a and 26b currently reside above and to theoutside (left and right) of end portions 48a and 48b, respectively.

FIG. 5 illustrates machine 10 and bag assembly 12 after a third stage,which occurs immediately after the second stage. In the third stage, EFAforks 24a and 24b have moved to their upper positions. In these upperpositions, the central regions of gaps 30 in forks 24 reside atapproximately the same vertical height as outer blades 26. All outerblades 26 and forks 24 are positioned vertically above center arm 22.This movement of forks 24 removes some of the droop in bag 42. However,the outermost regions of end portions 48a and 48b now extend verticallydownward through and past gaps 80, which define the horizontal spacesbetween outer blades 26 and corresponding forks 24.

FIG. 6 illustrates machine 10 and bag assembly 12 after a fourth stage,which occurs immediately after the third stage. In the fourth stage,vacuum is applied to bag 42 through valve 54 (see FIG. 1) and passage128 (see FIG. 2). Outer blades 26a and 26b move into, or mesh with, gaps30 in forks 24a and 24b, respectively. Bends, folds, or pleats 82a, 82b,84a, and 84b are formed in end portions 48 of bag 42 as a result of thisrelative movement between outer blades 26 and forks 24.

In particular, as outer blades 26 move into gaps 30, the outermostregions of end portions 48 are tucked between tines 28 of forks 24. Themuch of the excess material of bag 42 that drooped vertically downwardpast gaps 80 after the third stage (see FIG. 5) is now drawn into gaps30. Only the very ends of bag 42 extend out and droop down from theentrance edges of forks 24. Moving from the outermost edges of bag 42inward, pleats 82a and 82b reside at leading edges 86a and 86b of outerblades 26a and 26b, respectively, as bag 42 bends back on itself and isjuxtaposed on opposing sides of blades 26a and 26b. Pleats 84a and 84breside at entrance edges 32 of tines 28a of forks 24a and 24b,respectively, as bag 42 bends back on itself again and is juxtaposed onopposing sides of tines 28a of forks 24a and 24b.

FIG. 7 illustrates machine 10 and bag assembly 12 after a fifth stage,which occurs immediately after the fourth stage. In the fifth stage,pleat clamps 34a and 34b, each with their fingers 36 opened to theirmaximum amount of extension, move inward toward the central portion 50of bag 42. In this stage, pleat clamps 34 each stop at theirintermediate positions. This causes the outer ends of bag 42 to befolded under forks 24. At the current point in the process, openings 38between fingers 36 are sufficiently wide to loosely accommodatecorresponding forks 24 and two thicknesses of bag 42. Inner tips 88 offingers 36 are now positioned around points vertically above and belowleading edges 86 of outer blades 26.

FIG. 8 illustrates machine 10 and bag assembly 12 after a sixth stage,which occurs immediately after the fifth stage. In the sixth stage,outer blade 26b is retracted from gap 30 in fork 24b by movinghorizontally outward. Outer blade 26a remains positioned within gap 30of fork 24a to reduce bag distortion in subsequent stages. The naturalstiffness of bag 42 along with the friction of bag 42 against interiorwalls of forks 24 causes bag 42 to remain within gap 30 of fork 24brather than be drawn outward with outer blade 26b. As shown in FIG. 8,the length of fingers 36 accommodates both fork 24b, outer blade 26b inits retracted state, and gap 80.

FIG. 9 illustrates machine 10 and bag assembly 12 after a seventh stage,which occurs immediately after the sixth stage. In the seventh stage,EFA 20, which includes outer blades 26, forks 24, and center arm 22 (seeFIG. 1), is removed from engagement with bag 42 by moving backward. Thevacuum previously applied to bag 42 along with the natural stiffness ofbag 42 prevents distortion of pleats 82 and 84 previously formed in bag42 or other significant disturbances of bag 42. At this point, the foldspreviously made in end portions 48 of bag 42 are supported by lowerfingers 36b of pleat clamps 34.

FIG. 10 illustrates machine 10 and bag assembly 12 after an eighthstage, which occurs immediately after the seventh stage. In the eighthstage, pleat clamp fingers 36 have been urged together by being moved totheir clamped position. In other words, a clamping force is exertedbetween fingers 36 thereby entrapping pleats 82 and 84 within fingers36. These clamping forces are sufficiently great to prevent anysubstantial inflation or other separation of the portions of bag 42residing within pleat clamps 34. This clamped portion of bag 42currently resides slightly above central portion 50 of bag 42.

FIG. 11 illustrates machine 10 and bag assembly 12 after a ninth stage,which occurs immediately after the eighth stage. In the ninth stage,blade 14 is moved downward into engagement with top section 46 of bag42. More particularly, blade 14 contacts top section 46 at centralportion 50 of bag 42. Bottom section 44 of bag 42, particularly atcentral portion 50 of bag 42, contacts plenums 59 due to the forceexerted by gravity and the vacuum previously applied to bag 42.

FIG. 12 illustrates machine 10 and bag assembly 12 after a tenth stagewhich occurs immediately after the ninth stage. In the tenth stage, thepreviously applied vacuum is removed from bag assembly 12 through valve54 and passage 128 (see FIGS. 1-3) and valve 54 is controlled to couplevent 58 (see FIG. 1) to passage 128 and bag assembly 12. At around thesame time, valve 55 (see FIGS. 1 and 3) is operated to couple vacuumreservoir 56 to the plenum of blade 14 and to plenums 59. The preferredembodiments contemplate the use of around 0.5 to 7 CFM of vacuumcapacity from reservoir 56, but this is not a critical parameter. Aftera short period of time, sufficient vacuum suction or pressure has beenapplied to the exteriors of top section 46 and bottom section 44 of bagassembly 12 through holes 114 and 122 of blade 14 and plenums 59,respectively, so that blade 14 and plenums 59 achieve a hold or grip ontop and bottom sections 46 and 44, respectively. When this happens,blade 14 is raised to its upward position, as illustrated in FIG. 12.

The raising of blade 14 pulls top section 46 from bottom section 44 inthe central portion 50 of bag assembly 12, causing top section 46 tobecome separated from bottom section 44 by pulling. The pulling of topand bottom sections 46 and 44 apart may be contrasted with pushing,which would occur if a positive air pressure were applied to theinterior of air bag 12. A relatively low volume of air enters bagassembly 12 through vent 58, valve 54, and passage 128 (see FIGS. 1-2).This air is desirably filtered or otherwise purified to reduce thelikelihood of contaminants from entering bag 42. By pulling top andbottom sections 46 and 44 apart rather than pushing them apart byinflating bag assembly 12, a smaller volume of air needs to be filteredor otherwise purified. Consequently, the degree of filtration orpurification which can be achieved at practical expense is increased.Moreover, machine 10 need not include pressure chambers and the like forproducing and storing pressurized air which might otherwise be needed infolding bag assembly 12. Consequently, the costs of machine 10 arereduced.

Of course, during this stage pleat clamps 34 prevent those portions ofbag 42 which are entrapped therein from becoming inflated by the airentering bag assembly 12 or otherwise separated. As blade 14 rises, topsection 46 moves upward. In fact, top section 46 now resides above theportions of bag 42 that are trapped within pleat clamps 34 while bottomsection 44 resides below the portions of bag 42 that are trapped withinpleat clamps 34. The shape of bag 42 is limited in the verticaldimension by plenums 59 on the bottom and blade 14 on the top.

FIG. 13 illustrates machine 10 and bag assembly 12 after an eleventhstage, which occurs immediately after the tenth stage. In the eleventhstage, pleat clamps 34 move further inward toward central portion 50 ofbag 42. Top blade 14 and plenums 59 prevent the bag from distortingoutward in the vertical dimension during this operation. Pleat clamps 34each stop at their extreme inward positions, in which inner tips 88 offingers 36 nearly touch each other but are still spaced a small distanceapart. Of course, the portions of bag 42 which have been entrappedwithin fingers 36 by clamping move inward with pleat clamps 34.Consequently, the entire edge portions 48 of bag 42 have been poked intothe central portion 50 of bag 42.

This eleventh stage reduces the interior volume of bag assembly 12 bytucking pleat clamps 34 between top and bottom sections 46 and 44. Sincetop and bottom sections 46 and 44 have been pulled apart, no positivepressure is applied to the interior of bag assembly 12. Consequently,when pleat clamps 34 are tucked into the interior volume of bag assembly12 air may easily escape bag assembly 12 through air passage 128. Thisprevents air pressures experienced by bag assembly 12 from becomingexcessive.

FIG. 14 illustrates machine 10 and bag assembly 12 after a twelfthstage, which occurs immediately after the eleventh stage. In the twelfthstage, valve 55 (see FIGS. 1 and 3) is controlled to remove vacuumpressure from blade 14 and from plenums 59, causing blade 14 to removeits suction hold or grip on top section 46 of bag assembly 12 andplenums 59 to remove their hold or grip on bottom section 44. Inaddition, valve 54 (see FIGS. 1 and 3) is again operated to apply vacuumto bag assembly 12 through passage 128 to deflate or otherwise collapsebag 42. In addition, pins 16 are moved downward through slots 39 inpleat clamp fingers 36. As pins 16 move downward, elastic bands 18stretch over the top of central portion 50 of bag 42. This stretching ofbands 18 exerts a corresponding downward force on top section 46 of bag42. As bag 42 deflates, this downward force removes any lingering vacuumhold on top section 42 from blade 14 and overcomes the natural stiffnessof bag 42, causing bag 42 to collapse and top section 46 to movedownward as vacuum is applied.

FIG. 15 illustrates machine 10 and bag assembly 12 after a thirteenthstage, which occurs immediately after the twelfth stage. In thethirteenth stage, fingers 36 of pleat clamps 34 are moved to theirintermediate state, in which clamping forces are removed and fingers 36are spaced only a small distance apart. In short, pleat clamps 34 areloosened, thereby abandoning the grip they previously had on theentrapped portions of bag 42.

FIG. 16 illustrates machine 10 and bag assembly 12 after a fourteenthstage, which occurs immediately after the thirteenth stage. In thefourteenth stage, pleat clamps 34 are disengaged from bag 42 by movinghorizontally outward. In this stage, clamps 34 are moved to theirextreme outward positions. Fingers 36 may additionally be moved to thepositions where they are spaced furthest apart in preparation for asubsequent folding process. Notches 39 (see FIG. 1) in fingers 36 permitthis outward movement while pins 16 remain in their downward position.Since clamps 34 had previously been loosened, scant frictional forcesoppose this retraction of pleat clamps 34. Thus, pins 16, the vacuumapplied to bag 42, and the natural stiffness of bag 42 together serve toprevent any significant disturbance of the folds previously formed inbag 42.

FIG. 17 illustrates machine 10 and bag assembly 12 after a fifteenthstage, which occurs immediately after the fourteenth stage. In thefifteenth stage, top blade 14, pins 16, and elastic bands 18 aredisengaged from bag assembly 12 primarily by raising top blade 14. Pins16 may additionally be retracted to their raised position in preparationfor a subsequent folding process.

As a result of the process described above, bag assembly 12 hasundergone a horizontal folding process. The resulting folded-bag profileis shown in cross section in FIG. 18. As shown in FIG. 18, bag 42 of bagassembly 12 fits within the profile defined by base plate 40. This foldpattern is desirable because it produces an effective deploymentpattern. In particular, a central joint region 90 together with top andbottom joints 92 and 94, respectively, cause bag assembly 12 to inflateevenly in a left-to-right direction while bag assembly 12 is expandingaway from plate 40. In addition, the overall folding process isperformed quickly.

FIGS. 19A-19F together illustrate vertical folds which may be performedeither manually or automatically to completely fold bag 42 onto theprofile defined by base plate 40. After vertical folds have beencompleted, folded bag assembly 12 is ready for installation in avehicle.

FIGS. 20A-20C together show an alternate preferred process for foldingair bag 12. FIGS. 20A-20C illustrate stages roughly equivalent to stagesten-twelve, discussed above in connection with FIGS. 11-13,respectively. In the stage illustrated in FIG. 20A, top and bottomplenums 14 and 59 have been brought into contact with top and bottomsections 46 and 44, respectively, of bag assembly 12. In the stageillustrated in FIG. 20B, valve 55 is operated to couple vacuum toplenums 14 and 59. When sufficient vacuum has built up, top plenum 14 israised, thereby pulling top section 46 of bag assembly 12 away frombottom section 44. In the stage illustrated in FIG. 20C, a folding blade34' advances sideways from edge portion 48 into the interior of air bag12 between top and bottom sections 46 and 44. The sideways advance ofblade 34' causes edge portion 48 to peel away from plenums 14 and 59 andto become tucked into the interior volume of bag assembly 12 between topand bottom sections 46 and 44. Since top and bottom sections 46 and 44have been pulled apart by vacuum suction rather than pushed apart by apositive inflation pressure, air is free to escape from bag assembly 12during the tucking operation.

In summary, the present invention provides an automated system forfolding air bags. An air bag can be installed on machine 10 in around 4seconds and then, under the direction and coordination of controller 60(see FIG. 3), folded in about 20 seconds. An additional 15-17 secondsare required for an operator to make the vertical folds and unloadmachine 10. Consequently, machine 10 and the process by which bagassemblies 12 are folded result in a system which quickly folds bags andachieves significant time savings over the conventional manual foldingprocess. Moreover, the automated nature of the system of the presentinvention leads to a consistent fold pattern. In other words, each bagis folded in substantially the same way as every other bag. Thisconsistent fold pattern achieves a desirable deployment pattern alongwith a small folded-bag profile, which is entirely contained within thearea of base plate 40. Furthermore, bag contamination is reduced becausea low volume of air is introduced to bag 42 when top and bottom sections46 and 44 are pulled apart, rather than being pushed apart by inflation.This low volume of air may easily be purified by filtering or otherwise.Moreover, air is free to exit the interior of bag assembly 12 during atucking operation because no positive air pressure is applied to bagassembly 12.

The present invention has been described above with reference topreferred embodiments. However, those skilled in the art will recognizethat changes and modifications may be made in these preferredembodiments without departing from the scope of the present invention.For example, the above description uses the terms left, right, forward,backward, top, bottom, up, down, raised, lowered, horizontal, vertical,and the like, for clarity to indicate relative direction with respect tothe figures. Those skilled in the art will understand that such relativeterms are used to clarify the description and do not limit the scope ofthe present invention to any particular orientation. These and otherchanges, modifications, or altered orientations which are obvious tothose skilled in the art are intended to be included within the scope ofthe present invention.

What is claimed is:
 1. A method of automatically folding an air baghaving top and bottom sections, said folding achieving a folded-bagprofile suitable for vehicular installation along with an effective bagdeployment upon a crash of said vehicle, said method comprising thesteps of:clamping said top and bottom sections together proximate asecond portion of said bag to substantially restrict separation of saidtop and bottom sections at said second portion, said clamping stepleaving a first portion of said bag unclamped; pulling said top sectionat said first portion of said bag from said bottom section at said firstportion of said bag; and inserting said second portion of said bag intosaid first portion between said top and bottom sections.
 2. A method asclaimed in claim 1 wherein said first portion of said bag is a centralportion of said bag and said second portion of said bag is an edgeportion of said bag, and said method additionally comprises, prior tosaid clamping step, the step of forming a first pleat in said edgeportion of said bag so that said clamping step substantially preventsbag separation proximate said first pleat.
 3. A method as claimed inclaim 2 wherein said bag cooperates with a fork having first and secondtines, each of said first and second tines having entrance edges spacedapart by a first gap, and with a blade having a leading edge and beingspaced apart from said first and second tine entrance edges by a secondgap, and said first pleat forming step comprises the steps of:extendingsaid edge portion of said bag through said second gap; and moving saidblade into said first gap to tuck said bag into said first gap and formsaid first pleat at said leading edge of said blade.
 4. A method asclaimed in claim 3 additionally comprising the step of removing saidfork and said blade from said bag.
 5. A method as claimed in claim 4wherein said removing step retracts said blade from said first gapbefore said fork is removed from said bag.
 6. A method as claimed inclaim 4 comprising the step of positioning, prior to removing said forkfrom said blade, a clamp having first and second spaced apart fingers sothat said first and second fingers reside on opposing sides of saidfork.
 7. A method as claimed in claim 6 wherein said clamping stepcomprises the step of urging said first and second fingers toward oneanother.
 8. A method as claimed in claim 2 additionally comprising,prior to said clamping step, the step of forming a second pleat in saidedge portion of said bag so that said clamping step substantiallyprevents bag separation proximate said second pleat.
 9. A method asclaimed in claim 8 wherein said bag cooperates with a fork having firstand second tines, each of said first and second tines having entranceedges spaced apart by a first gap, and with a blade having a leadingedge and being spaced apart from said first and second tine entranceedges by a second gap, and said method additionally comprises the stepsof:extending a first edge portion of said bag through said second gap;juxtaposing a second edge portion of said bag with said first tine ofsaid fork; and moving said blade into said first gap to tuck said baginto said first gap and form said first pleat at said leading edge ofsaid blade and said second pleat at said entrance edge of said firsttine.
 10. A method as claimed in claim 1 wherein said clamping step isperformed by a clamp having first and second fingers clamped togetherfrom opposing sides of said second portion of said bag, and saidinserting step comprises the step of moving said clamp toward said firstportion of said bag.
 11. A method as claimed in claim 10 wherein saidfirst and second fingers impose a clamping force on said bag, and saidmethod additionally comprises, after said inserting step, the stepsof:collapsing said bag; removing said clamping force between saidfingers and said bag; and moving said clamp away from said first portionof said bag to disengage said clamp from said bag.
 12. A method asclaimed in claim 1 wherein said pulling step comprises the stepsof:holding said top section with a first member; holding said bottomsection with a second member; and moving one of said first and secondmembers away from the other of said first and second members.
 13. Amethod as claimed in claim 12 wherein said holding said top section stepcomprises the step of applying vacuum to said top section of said firstmember.
 14. An apparatus for automatically folding an air bag having topand bottom sections throughout first and second portions of said bag,said folding achieving a folded-bag profile suitable for vehicularinstallation along with an effective bag deployment upon a crash of saidvehicle, said apparatus comprising:a controller for coordinating foldingoperations; pleat clamp, coupled to said controller, for clamping saidtop and bottom sections of said bag together proximate said secondportion of said bag; means, coupled to said controller, for pulling saidtop section at said first portion of said bag from said bottom sectionat said first portion of said bag; and means, coupled to saidcontroller, for inserting said second portion of said bag into saidfirst portion of said bag between said top and bottom sections.
 15. Anapparatus as claimed in claim 14 wherein said first portion of said bagis a central portion of said bag and said second portion of said bag isan edge portion of said bag, and said apparatus additionally comprises,means, coupled to said controller, for forming a first pleat in saidedge portion of said bag.
 16. An apparatus as claimed in claim 15wherein said first pleat forming means comprises:a fork having first andsecond tines, each having entrance edges, spaced apart by a first gap; ablade having a leading edge and being spaced apart from said first andsecond tine entrance edges by a second gap; means for extending saidedge portion of said bag through said second gap; and means for movingsaid blade into said first gap so that, when said edge portion of saidbag is extended through said second gap, said bag is tucked into saidfirst gap, and said first pleat is formed at said leading edge of saidblade.
 17. An apparatus as claimed in claim 15 wherein said pleat clampcomprises:first and second fingers; and means, responsive to saidcontroller, for clamping said first and second fingers together fromopposing sides of said edge portion of said bag.
 18. An apparatus asclaimed in claim 15 wherein said air bag has a second edge portion on anopposing side of said central portion from said edge portion, and saidapparatus additionally comprises:a second pleat clamp, coupled to saidcontroller, for clamping said top and bottom sections of said bagtogether proximate said second edge portion of said bag; and means,coupled to said second pleat clamp and said controller, for insertingsaid clamped second edge portion into said central portion between saidtop and bottom sections.
 19. An apparatus as claimed in claim 14additionally comprising means, coupled to said controller for collapsingsaid air bag.
 20. An apparatus as claimed in claim 14 wherein saidpulling means comprises:first holding means coupled to said controller,said first holding means being configured to hold said top section ofsaid bag; second holding means coupled to said controller, said secondholding means being configured to hold said bottom section of said bag;and moving means coupled to said controller, said moving means causingat least one of said first and second holding means to move away fromthe other of said first and second holding means.
 21. A method ofautomatically folding an air bag having top and bottom sections, saidfolding achieving a folded-bag profile suitable for vehicularinstallation along with an effective bag deployment upon a crash of saidvehicle, said method comprising the steps of:spacing a fork having firstand second tines, each having entrance edges, apart by a first gap froma blade having a leading edge, said spacing positioning said bladeleading edge apart from said first and second tine entrance edges by asecond gap; extending a first section of an edge portion of said bagthrough said second gap; juxtaposing a second section of said edgeportion of said bag with said first tine of said fork; and moving saidblade into said first gap to tuck said first section of said bag intosaid first gap and form a first pleat at said leading edge of said bladeand a second pleat at said entrance edge of said first tine; clampingsaid top and bottom sections of said bag together proximate said edgeportion of said bag to substantially restrict separation of said top andbottom sections at said edge portion, said clamping step leaving acentral portion of said bag unclamped; pulling said top section at saidcentral portion of said bag from said bottom section at said centralportion of said bag; and inserting said clamped edge portion into saidcentral portion between said top and bottom sections; and collapsingsaid bag.
 22. A method as claimed in claim 21 comprising the step ofpositioning, prior to said clamping step, a clamp having first andsecond spaced apart fingers so that said first and second fingers resideon opposing sides of said fork, bag, and blade.
 23. A method as claimedin claim 22 additionally comprising, after said positioning step, thesteps of:first, retracting said blade from said first gap to disengagesaid blade from said bag; second, retracting said fork from said bag;and third, removing said blade and said fork from within said clamp.